1. Field of the Invention
Embodiments of the present invention relate to an energy storage system (ESS) using an uninterruptible power supply (UPS).
2. Description of the Related Art
An energy storage system (ESS) according to the related art includes a battery for the ESS and a power conditioning system (PCS), and connects to a high voltage, for example, 22.9 kV power line supplied from a grid. Here, a vacuum circuit breaker (VCB), a transformer (TR), and an air circuit breaker (ACB) are to be installed for high voltage connection.
Although a high voltage connector band having a required capacity is already provided when configuring a load of a building or factory, additional power equipment needs to be installed to connect the VCR, the transformer, and the ACB to the PCS. In addition, the ESS is not considered at a stage of designing the construction of a building and thus, it is difficult to verify the effect of the high voltage connector band with respect to the entire power system.
In particular, voltage distortion may occur when driving the power equipment, for example, the PCS of the ESS. In addition, a voltage may irregularly vary during a voltage stabilization period required when the PCS starts to supply power and suspends the power supply.